This proposal is for continued support of our Bioengineering Research Partnership entitled Biology, Biomechanics and Atherosclerosis. Over the first 4 years of our BRP funding, our group has focused on obtaining a better understanding of the basic mechanism of atherosclerosis with a particular focus on the interrelationships between biomechanical forces and atherosclerosis. Our initial efforts have been broad in scope incorporating the expertise of engineers, biologists and clinicians from an expansive range of clinical and academic areas. In this, our request for continued support, we have elected to focus our efforts on a single atherosclerotic disease entity, abdominal aortic aneurysms (AAA). We have taken this approach based on several factors including the importance of the clinical problem, the development of extensive, relevant preliminary data by members of the BRP and the potential benefit of having a greater focus for the members of the BRP. The overall goal of this BRP is to gain a better understanding of the biology and biomechanics of AAA formation with the overall goal of gaining new insights into the underlying mechanisms of AAA development. This project is support my novel data from the members of this BRP that implicate additional protein families in the maladaptive remodeling of the aortic wall that occurs during AAA formation. This proposal will focus on developing aneurysms at the earliest stages of remodeling so as to study the most biologically relevant aspects of AAA formation.